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OBJECTIVE: This study aimed to investigate the feasibility of using dual-layer spectral CT multi-parameter feature to predict microvascular invasion of hepatocellular carcinoma. METHODS: This retrospective study enrolled 50 HCC patients who underwent multiphase contrast-enhanced spectral CT studies preoperatively. Combined clinical data, radiological features with spectral CT quantitative parameter were constructed to predict MVI. ROC was applied to identify potential predictors of MVI. The CT values obtained by simulating the conventional CT scans with 70âkeV images were compared with those obtained with 40âkeV images. RESULTS: 50 hepatocellular carcinomas were detected with 30 lesions (Group A) with microvascular invasion and 20 (Group B) without. There were significant differences in AFP,tumer size, IC, NIC,slope and effective atomic number in AP and ICrr in VP between Group A ((1000(10.875,1000),4.360±0.3105, 1.7750 (1.5350,1.8825) mg/ml, 0.1785 (0.1621,0.2124), 2.0362±0.2108,8.0960±0.1043,0.2830±0.0777) and Group B (4.750(3.325,20.425),3.190±0.2979,1.4700 (1.4500,1.5775) mg/ml, 0.1441 (0.1373,0.1490),1.8601±0.1595, 7.8105±0.7830 and 0.2228±0.0612) (all pâ<â0.05). Using 0.1586 as the threshold for NIC, one could obtain an area-under-curve (AUC) of 0.875 in ROC to differentiate between tumours with and without microvascular invasion. AUC was 0.625 with CT value at 70âkeV and improved to 0.843 at 40âkeV. CONCLUSION: Dual-layer spectral CT provides additional quantitative parameters than conventional CT to enhance the differentiation between hepatocellular carcinoma with and without microvascular invasion. Especially, the normalized iodine concentration (NIC) in arterial phase has the greatest potential application value in determining whether microvascular invasion exists, and can offer an important reference for clinical treatment plan and prognosis assessment.
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BACKGROUND: To explore the clinical value of energy spectrum curves of dual-energy computer tomography (CT) in quantitative evaluation of different pathological grades of gastric adenocarcinoma. METHODS: A total of 62 patients with 36 poorly, 25 moderately and 1 well differentiated gastric adenocarcinomas confirmed pathologically were collected. Dual-energy CT plain and enhanced scanning were undergone before operation. Dual-Energy software was used to measure the slope of the energy spectrum curves (λ) in arterial and venous phases (VPs) after image reconstruction. Patients were divided into two groups according to the pathological results, including well and moderately differentiated gastric adenocarcinoma group and poorly differentiated gastric adenocarcinoma group. Data of each group were analyzed by independent sample t-test. Receiver operating characteristic curve (ROC) was used to evaluate the diagnostic efficiency of the corresponding parameters. RESULTS: There were significant differences in λ values of 40-50, 40-60, 40-80, 40-90, 40-100, 40-120, 40-130, 40-140 and 40-150 keV energy ranges in VP between the well and moderately differentiated group and poorly differentiated group (P<0.05), but no significant differences in λ values of different energy ranges in arterial phase (AP) between the two groups (P>0.05). And the area under curve in 40-120 keV energy range was the largest in VP. λ40-120keV=2.69 was selected as the diagnostic threshold with the maximum Youden index, the sensitivity and specificity were 61.1% and 76%, respectively. CONCLUSIONS: The energy spectrum curve of dual-energy CT had certain diagnostic value in the quantitative evaluation of pathological grading of gastric adenocarcinoma.
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Objective To determine the utility of single energy CT value and spectrum energy curve in identifying different cause of diffuse spleen enlargement.Methods 43 patients confirmed by either surgical pathology,aspiration biopsy or clinical comprehensive diagnosis and follow-up were assessed,including lymphoma with spleen infiltration(lymphoma group,n=18) and cirrhotic splenomegaly(liver cirrhosis group,n=25).All patients underwent upper abdomen CT scans in GSI mode and the GSI data were transferred to the Workstation AW 4.6 to acquire single energy CT value(40-140 keV,10 keV's interval) and spectrum energy curve of the spleen on the venous phase.All single energy CT values and the slope of curves were comparatively analyzed through independent-samples t test.The diagnostic efficiency were evaluated by ROC analysis.Results Under 40-140 keV energy range,single energy CT values were significantly lower in the lymphoma group than in the liver cirrhosis group(all P＜0.05).The spectrum energy curve were both types of decreasing.Under 40-90 keV,100-140 keV energy range,the slop of curves in the lymphoma group(2.42 ± 0.70,0.27± 0.08) were also significantly lower than in the liver cirrhosis group (3.11 ± 0.62,0.34± 0.07),respectively(all P ＜0.05).When the slope of curve under 40-90 keV energy range was selected as a diagnostic indicator,the area under the curve(AUC) would reach 0.77.If threshold value of 1.39 was taken,the sensitivity and specificity would be equal to 86 ％ and 64 ％,respectively.Conclusion Single energy CT value and spectrum energy curve are helpful for differentiation of lymphoma with spleen infiltration from cirrhotic splenomegaly.
